Police found a dead dog in my brothers flat England uk?

my brother has his own flat but has not been staying there for over three months he is cled as disabled so he has key workers ect, well my brother had not contacted his key workers for nearly a month and they got worried so the police broke into his flat and inside found a dead dog and said it looks like squatters have been in there. Now they have contacted my brother by phone and told him to remove the dog who should he contact? we do not know how long it has been dead or anything in england help please